The first astronomers mapped the movement of the seasons and used the positions of the constellations for augurs and astrology; today astronomy probes ever deeper into the nature of life and reality itself. In this general overview, astrophysicist J.P. McEvoy chronicles how our knowledge of the cosmos has developed, beginning with Stonehenge and ending with the current debate on string theory. He arrays many of the greatest discoveries of all time and such scientific and philosophical personalities as Aristotle, Copernicus, Newton, Einstein, Eddington, and Hawking. McEvoy makes the argument that astronomy is a science of observation and experiment rather than models and mathematics, and that much of current thinking is too reliant on unprovable conjecture.